Search PubMed⌕ Search

Biomedical subjects

Aaron B Caughey

Publications and source records attributed to Aaron B Caughey.

At least 37 records · Page 2Linked to original sources
PubMed2006

Induction of labor and cesarean delivery by gestational age.

OBJECTIVE: Studies of cesarean delivery (CD) rates among women undergoing induction of labor (IOL) often compare such women to women experiencing spontaneous labor at similar gestational ages. We sought to examine the association between IOL at various gestational ages and CD, accounting for the effect of increased gestational age among the comparison group who were managed expectantly. STUDY DESIGN: We conducted a retrospective cohort study of all term, singleton, cephalic presentation pregnancies delivered at our institution over 15 years excluding cesarean deliveries before labor. For each gestational age of induction, we created a comparison group of women who were undelivered at that gestational age, and who experienced labor at some future gestational age. RESULTS: In women undergoing IOL at 38 weeks gestation, the CD rate was 11.9% as compared to 13.3% (P = .42) of women beyond 38 weeks gestation. The CD rate for induction of labor compared to ongoing pregnancy was 14.3% versus 15.0% (P = .62) at 39 weeks, 20.4% versus 19.0% (P = .41) at 40 weeks, and 24.3% versus 26.0% (P = .39) at 41 weeks. When controlling for potential confounding, there was a higher rate of CD among women with expectant management beyond 38 weeks (adjusted odds ratio [AOR] 1.80; 95% CI 1.29-2.53), 39 weeks (1.39; 95% CI 1.08-1.80), and 40 weeks (AOR 1.27; 95% CI 1.00-1.62). CONCLUSION: Our findings suggest that IOL may not increase a woman's risk of CD when compared to expectant management. While this question has been addressed prospectively at 41 weeks gestation, it requires further examination at earlier gestations and among various subgroups.

Cesarean Section↗
PubMed2006

Associated factors and outcomes of persistent occiput posterior position: A retrospective cohort study from 1976 to 2001.

OBJECTIVE: To identify maternal and fetal risk factors associated with persistent occiput posterior position at delivery, and to examine the association of occiput posterior position with subsequent obstetric outcomes. METHODS: This is a retrospective cohort study of 30 839 term, cephalic, singleton births. Women with persistent occiput posterior (OP) position at delivery were compared to those with occiput anterior (OA) position. Demographics, obstetric history, and labor management were evaluated and subsequent obstetric outcomes examined. Potential confounding variables were controlled for using multivariate logistic regression analysis. RESULTS: The overall frequency of OP position was 8.3% in the study population. When compared to Caucasians, a higher rate of OP was observed among African-Americans (OR = 1.4, 95% CI 1.25-1.64) while no other racial/ethnic differences were noted. Other associated factors included nulliparity, maternal age > or =35, gestational age > or =41 weeks, and birth weight >4000 g, as well as artificial rupture of the membranes (AROM) and epidural anesthesia (p < 0.001 for all). Persistent OP was associated with increased rates of operative vaginal (OR = 4.14, 95% CI 3.57-4.81) and cesarean deliveries (OR = 13.45, 95% CI 11.94-15.15) and other peripartum complications including third or fourth degree perineal lacerations (OR = 2.38, 95% CI 2.03-2.79), and chorioamnionitis (OR = 2.10, 95% CI 1.81-2.44). CONCLUSION: Epidural use, AROM, African-American ethnicity, nulliparity, and birth weight >4000 g are associated with persistent OP position at delivery, with higher rates of operative deliveries and obstetric complications. This information can be useful in counseling patients regarding risks and associated outcomes of persistent OP position.

Adult↗
PubMed2006

Screening or diagnostic: markedly elevated glucose loading test and perinatal outcomes.

OBJECTIVE: To determine the diagnostic value of markedly elevated 50-g glucose loading test results (>or=200 mg/dL) and associated perinatal outcomes. METHOD: This was a retrospective cohort study of 14 771 pregnancies screened for gestational diabetes mellitus (GDM) between 1988 and 2001. The positive predictive value of the 50-g oral glucose loading test (GLT) results as measured by plasma glucose value was examined. Perinatal outcomes were assessed for women with GLT results >or=200 mg/dL compared to GLT <200 mg/dL, stratified by the diagnosis of GDM. Statistical comparisons were made using the Chi-square test and Student's t-test and potential confounding factors were controlled for using multivariable logistic regression analyses. A p value <0.05 and 95% confidence intervals were used to indicate statistical significance. RESULTS: The positive predictive values for a GDM diagnosis were 62% for GLT results between 180 and 189 mg/dL, 79% for those between 200 and 209 mg/dL, and 100% for GLT results >or=230 mg/dL. Compared to women with a GLT result <200 mg/dL, among women not diagnosed with GDM but with a GLT >or=200 mg/dL the adjusted odds ratio (aOR) for cesarean delivery was 4.18 (95% confidence intervals, 1.15-15.2). These women also had higher aORs for preterm delivery <32 weeks (aOR = 8.05 (1.02-63.6)), shoulder dystocia (aOR = 15.14 (1.64-140)), and their neonates were more likely to have a 5-minute Apgar score <7 (aOR = 6.41 (1.23-33.3)). For women diagnosed with GDM and with a GLT >or=200 mg/dL, the aOR for cesarean delivery was also elevated compared to those with a GLT <200 mg/dL (aOR = 2.24 (1.19-4.21)). CONCLUSION: A GLT value of >or=200 mg/dL is not absolutely diagnostic for gestational diabetes but is associated with unfavorable perinatal outcomes.

Cohort Studies↗
PubMed2006

Obstetric outcomes in women with sonographically identified uterine leiomyomata.

OBJECTIVE: To examine the association between leiomyomata and complications during pregnancy, delivery, and the puerperium. METHODS: We conducted a retrospective cohort study comparing pregnancy outcomes in women with and without uterine leiomyomata who underwent routine second trimester obstetric ultrasonography and delivered viable infants at a single institution. Potential confounding variables, including maternal age, weight, ethnicity, parity, gestational age, epidural use, and labor induction, were controlled for using multivariate logistic regression techniques. RESULTS: From 1993 to 2003, 15,104 women underwent routine second trimester prenatal ultrasonography, and 401 (2.7%) women were identified with at least 1 leiomyoma. By univariate and multivariate analyses, the presence of leiomyomata was associated with increased risks for cesarean delivery (adjusted odds ratio [AOR] 1.57, 95% confidence interval [CI] 1.16-2.13), breech presentation (AOR 1.64, 95% CI 1.11-2.40), malposition (AOR 1.59, 95% CI 1.18-2.15), preterm delivery (AOR 1.45, 95% CI 1.08-1.96), placenta previa (AOR 1.86, 95% CI 1.02-3.39), and severe postpartum hemorrhage (AOR 2.57, 95% CI 1.54-4.27). Premature rupture of membranes, operative vaginal delivery, chorioamnionitis, and endomyometritis were not associated with leiomyomata. Median length of labor was not different between the 2 groups. When compared with leiomyomata less than 10 cm in size, leiomyomata 10 cm or larger were associated with rates of cesarean delivery that were not statistically different (25% compared with 31%, P = .49). CONCLUSION: Pregnant women with leiomyomata are at increased risk for cesarean delivery, breech presentation, malposition, preterm delivery, placenta previa, and severe post partum hemorrhage. Women with leiomyomata 10 cm or larger achieve a vaginal delivery rate of nearly 70%. These results are useful for preconception and prenatal counseling of women with leiomyomata. LEVEL OF EVIDENCE: II-2.

Adult↗
PubMed2006

The association between persistent occiput posterior position and neonatal outcomes.

OBJECTIVE: To examine the effect of persistent occiput posterior position on neonatal outcome. METHODS: This is a retrospective cohort study of 31,392 term, cephalic, singleton births. Women with neonates born in persistent occiput posterior position at delivery were compared to those with occiput anterior position. Women with occiput transverse position were excluded. The association between occiput posterior position and neonatal outcomes, including 5-minute Apgar scores, umbilical cord gases, meconium-stained amniotic fluid, meconium aspiration syndrome, birth trauma, admission to the intensive care nursery, and length of stay were examined using chi(2) and Student t tests. Potential confounders (maternal age, ethnicity, parity, gestational age, epidural anesthesia, labor induction, length of labor, meconium, chorioamnionitis, birth weight, and year of delivery) were controlled for by using multivariable logistic regression and linear regression analyses. RESULTS: There were 2,591 (8.2%) neonates delivered in occiput posterior position of the total cohort of 31,392 deliveries. Compared with occiput anterior, neonates delivered in occiput posterior position had higher risks for adverse outcomes, including 5-minute Apgar score less than 7 (odds ratio [OR] 1.50, 95% confidence interval [CI] 1.17-1.91), acidemic umbilical cord gases (OR 2.05, 95% CI 1.52-2.77), meconium-stained amniotic fluid (OR 1.29, 95% CI 1.17-1.42), birth trauma (OR 1.77, 95% CI 1.22-2.57), admission to the intensive care nursery (OR 1.57, 95% CI 1.28-1.92), and longer neonatal stay in the hospital (OR 2.69, 95% CI 2.22-3.25). CONCLUSION: Persistent occiput posterior position at delivery is associated with higher risks of adverse neonatal outcomes compared with neonates delivered in the occiput anterior position. This information may be important in counseling women who experience persistent occiput posterior position in labor. LEVEL OF EVIDENCE: II-2.

Adult↗
PubMed2006

History of miscarriage and increased incidence of fetal aneuploidy in subsequent pregnancy.

OBJECTIVE: The purpose of this study was to examine the association between history of spontaneous abortion and aneuploidy in a subsequent pregnancy. METHODS: This was a retrospective cohort study of women who underwent fetal karyotype analysis with amniocentesis or chorionic villus sampling at a single prenatal diagnosis center. Information on spontaneous abortions, parity, maternal age, ethnicity, type of prenatal diagnosis, and karyotype was assessed. Univariable and multivariable analyses were conducted. RESULTS: A total of 46,939 women were included in our analysis. Women with no prior spontaneous abortions had a 1.39% risk for any aneuploidy. In women with one prior spontaneous abortion, this risk increased to 1.67%; for women with 2 previous spontaneous abortions, the risk increased to 1.84%; and for those women who had had 3 or more prior spontaneous abortions, the risk increased further to 2.18% (P < .007). When controlling for maternal age, parity, ethnicity, and mode of prenatal diagnosis and compared with women with no prior spontaneous abortions, women with one prior spontaneous abortion (adjusted odds ratio [AOR] 1.21, 95% confidence interval [CI] 1.01-1.47) or 3 or more prior spontaneous abortions (AOR 1.51, 95% CI 1.02-2.25) had a statistically significant increase in aneuploidy in a subsequent pregnancy. Women with 2 prior spontaneous abortions had an AOR of 1.26 for aneuploidy, but the 95% CI contained unity. CONCLUSION: An increased risk of karyotypic abnormality identified at the time of prenatal diagnosis is demonstrated in patients with an increasing number of spontaneous abortions. This study provides information regarding this risk among women presenting for prenatal diagnosis. According to our data, for a woman with an a priori risk of 1 in 300 for Down syndrome, 3 prior spontaneous abortions would increase that risk by 47% to 1 in 204. These results should be confirmed in low-risk populations.

Abortion, Spontaneous↗
PubMed2006

Gestational weight gain and adverse neonatal outcome among term infants.

OBJECTIVE: To examine the relationship between gestational weight gain and adverse neonatal outcomes among infants born at term (37 weeks or more). METHODS: This was a retrospective cohort study of 20,465 nondiabetic, term, singleton births. We performed univariable and multivariable analyses of the associations between gestational weight gain and neonatal outcomes. We categorized gestational weight gain by the Institute of Medicine guidelines as well as extremes of gestational weight gain (less than 7 kg and more than 18 kg). RESULTS: Gestational weight gain above the Institute of Medicine guidelines was more common than gestational weight gain below (43.3% compared with 20.1%). In multivariable analyses, gestational weight gain above guidelines was associated with a low 5-minute Apgar score (adjusted odds ratio [AOR] 1.33, 95% confidence interval [CI] 1.01-1.76), seizure (AOR 6.50, 95% CI 1.43-29.65), hypoglycemia (AOR 1.52, 95% CI 1.06-2.16), polycythemia (AOR 1.44, 95% CI 1.06-1.94), meconium aspiration syndrome (AOR 1.79, 95% CI 1.12-2.86), and large for gestational age (AOR 1.98, 95% CI 1.74-2.25) compared with women within weight gain guidelines. Gestational weight gain below guidelines was associated with decreased odds of neonatal intensive care unit admission (AOR 0.66, 95% CI 0.46-0.96) and increased odds of small for gestational age (SGA; AOR 1.66, 95% CI 1.44-1.92). Gestational weight gain less than 7 kg was associated with increased risk of seizure, hospital stay more than 5 days, and SGA. Gestational weight gain more than 18 kg was associated with assisted ventilation, seizure, hypoglycemia, polycythemia, meconium aspiration syndrome, and large for gestational age. CONCLUSION: Gestational weight gain above guidelines was common and associated with multiple adverse neonatal outcomes, whereas gestational weight gain below guidelines was only associated with SGA status. Public health efforts among similar populations should emphasize prevention of excessive gestational weight gain.

Analysis of Variance↗
PubMed2006

Cost of transferring one through five embryos per in vitro fertilization cycle from various payor perspectives.

OBJECTIVE: We sought to examine the costs of transferring one through five embryos per in vitro fertilization cycle from each of three perspectives: society, the infertile couple, and the insurer. METHODS: Data from the 2003 Assisted Reproductive Technology Report was used to create Markov decision analytic models stratified by maternal age subgroup. We modeled both total costs, cost-effectiveness (cost per live birth), and clinical outcomes: multiple births, preterm deliveries, and cerebral palsy. RESULTS: From a societal and insurer perspective, it was least expensive to transfer one embryo. For women aged younger than 35 years, it cost society 80% more to transfer five rather than one embryo at a time (total cost 39,212 dollars compared with 21,661 dollars). For women aged older than 42 years, it cost 13% more (29,102 dollars compared with 25,723 dollars). From a parental perspective, it was least expensive to transfer between two and five embryos, depending on maternal age. One-embryo transfers markedly improved clinical outcomes. For example, two compared with one-embryo transfers for women aged younger than 35 years reduced preterm birth and cerebral palsy rates by 55% and 41%, respectively. Univariable sensitivity analysis and Monte Carlo simulation showed our results to be robust. CONCLUSION: Transferring one embryo per cycle is the least expensive strategy from a societal perspective, especially for younger women, yet it is the most expensive option from a parental perspective. To reduce in vitro fertilization-associated multiple birth rates, public policy must address these disparate financial incentives.

Adult↗
PubMed2006

Chorionic villus sampling compared with amniocentesis and the difference in the rate of pregnancy loss.

OBJECTIVE: To compare loss rates following amniocentesis and chorionic villus sampling (CVS) over time. METHODS: A retrospective cohort study of all amniocentesis and CVS procedures resulting in a normal karyotype from 1983-2003 at a single prenatal diagnostic referral center was conducted. Pregnancy loss rates for amniocentesis, CVS, and nonintervention groups (ie, those who had nuchal translucency screening or counseling, but no procedure) were compared using the chi 2 test. Year of procedure, maternal age, parity, race or ethnicity, and gestational age at procedure were controlled for in multivariable logistic regression models. RESULTS: There were 9,886 CVS and 30,893 amniocentesis procedures performed during the study period that resulted in a normal karyotype. The overall loss rates were 3.12% for CVS and 0.83% for amniocentesis (P < .001). When examined by 5-year intervals, there was a statistically significant decrease in the CVS loss rate (P < .001) and a nonsignificant lesser decrease in the loss rate for amniocentesis over time. Although the pregnancy loss rate from CVS over the entire study period was higher than from amniocentesis (adjusted odds ratio 4.23, 95% confidence interval 2.29-7.81), in the most recent time period, 1998 to 2003, there was no difference between the two procedures (adjusted odds ratio 1.03, 95% confidence interval 0.23-4.52). CONCLUSION: The loss rates for both amniocentesis and CVS at our institution have decreased over time. Because the decrease in loss rate for CVS has been greater, there is no longer a statistically significant difference between the two. These results are informative in both patient counseling and establishing widespread prenatal diagnostic and screening programs.

Abortion, Spontaneous↗
PubMed2006

Weight gain and spontaneous preterm birth: the role of race or ethnicity and previous preterm birth.

OBJECTIVE: To study how the relationship between gestational weight gain and spontaneous preterm birth interacts with maternal race or ethnicity and previous preterm birth status. METHODS: This was a retrospective cohort study of singleton births to women of normal or low prepregnancy body mass index. Gestational weight gain was measured as total weight gain divided by weeks of gestation at delivery, and weight gain was categorized as low (less than 0.27 kg/wk,), normal (0.27-0.52 kg/wk), or high (more than 0.52 kg/wk). Univariable and multivariable analyses were performed on the relationship between weight gain categories and spontaneous preterm birth, stratified by maternal race or ethnicity and history of previous preterm birth. RESULTS: Overall, low weight gain was associated with spontaneous preterm birth (adjusted odds ratio [AOR] 2.5, 95% confidence interval [CI] 2.0-3.1). Although low gain was consistently associated with increased spontaneous preterm birth, some differences were found in subgroup analysis. Among African Americans with a previous preterm birth, both low and high weight gain were associated with increased odds of spontaneous preterm birth (AOR for low weight gain 4.3, 95% CI 1.2-15.5; AOR for high weight gain 6.1, 95% CI 1.8-20.2). For all other groups, high weight gain was not associated with spontaneous preterm birth. Among Asians with a previous preterm birth, low weight gain was not statistically significantly associated with spontaneous preterm birth (AOR 1.9, 95% CI 0.5-7.7). Among Asians there was also a non-statistically significant inverse relationship between high weight gain and spontaneous preterm birth (AOR 0.5, 95% CI 0.3-1.1). CONCLUSION: These results confirm an association between low maternal weight gain and spontaneous preterm birth. The effect modification of maternal race or ethnicity and history of previous preterm birth on this association deserves further study. LEVEL OF EVIDENCE: II-2.

Adult↗
PubMed2005

Preimplantation genetic diagnosis: the earliest form of prenatal diagnosis.

Preimplantation genetic diagnosis (PGD) can provide genetic information on embryos obtained through in vitro fertilization (IVF), allowing implantation of embryos identified as unaffected with a given genetic or chromosomal disorder. With the availability of increasingly sophisticated genetic testing, its use has advanced from the selection of female embryos for the prevention of X-linked genetic diseases to testing for single gene disorders via PCR. Recently, PGD has also been used in the setting of assisted reproductive technology to select for chromosomally normal embryos in an effort to increase the rates of implantation and successful pregnancy. As the number of patients undergoing IVF increases, the indications for its use broadens, and more mutations underlying genetic disorders are identified, PGD is becoming more widespread. As this evolution continues, recognition of the limitations of PGD, as well as ethical concerns regarding use and misuse of this technology, need to be considered by patients, clinicians, and policy makers.

Cytogenetic Analysis↗
PubMed2005

Cost-effectiveness analysis of prenatal diagnosis: methodological issues and concerns.

With increasing concerns regarding rapidly expanding health care costs, cost-effectiveness analysis (CEA) provides a methodology to assess whether marginal gains from new technology are worth the increased costs. In the arena of prenatal diagnosis, particular methodological and ethical concerns include whether the effects of such testing on individuals other than the patient are included, how termination of pregnancy is included in the models, redundancy of screening and diagnostic methods, and how screening may reassure or cause anxiety in patients depending on their results. The existing literature has demonstrated cost-effectiveness of screening and diagnosis of neural tube defects, Down syndrome, and cystic fibrosis in the general population. Screening for genetic disorders which have a higher prevalence among particular groups has also been shown to be cost effective, including diseases such as hemoglobinopathies and Tay-Sachs disease. Understanding the methodology and salient issues of CEA is critical for researchers, editors and clinicians to accurately interpret results of the growing body of cost-effectiveness studies in prenatal diagnosis.

Cost-Benefit Analysis↗
PubMed2005

Neonatal complications of term pregnancy: rates by gestational age increase in a continuous, not threshold, fashion.

OBJECTIVE: The purpose of this study was to determine whether, when, and how rates of short-term neonatal complications increase beyond 37 weeks of gestation. STUDY DESIGN: A retrospective cohort study was conducted of all low-risk, term, cephalic, and singleton births that were delivered at the University of California, San Francisco, between 1976 and 2001. Primary outcomes included neonatal umbilical artery pH, umbilical artery base excess, the presence of meconium, macrosomia, 5-minute Apgar scores, and admission to the intensive care nursery. Multivariate analyses were performed that controlled for maternal ethnicity, weight, age, socioeconomic status, and obstetric history. RESULTS: Among the 32,679 women who were delivered at > or =37 completed weeks of gestation, the rates of umbilical artery pH <7.0, umbilical artery base excess less than -12 increased beyond 40 weeks of gestation, and the presence of meconium increased beyond 39 weeks of gestation (chi-squared test; P < .001). These outcomes continued to increase in each subsequent week, and these findings persisted when they were controlled for potential confounders in multivariate models. CONCLUSION: We found that the rates of immediate neonatal morbidity increase with increasing gestational age. Accurate determination of these rates is important in the determination of gestational age at which the risk of continuing the pregnancy outweighs the risk of induction of labor.

Adult↗
PubMed2005

Racial/ethnic differences in perineal, vaginal and cervical lacerations.

OBJECTIVE: To determine if variation exists between ethnicities for risk of perineal, vaginal, and cervical laceration at vaginal delivery. STUDY DESIGN: Retrospective cohort study of nulliparous women who underwent vaginal delivery of a vertex presentation. Predictor variable was ethnicity with outcome variables cervical, vaginal, and second-, third-, or fourth-degree perineal laceration. Logistic regression analysis was conducted to control for confounders. RESULTS: Of the 17,216 who met criteria, Filipino (OR = 1.92, 95% CI 1.64-2.25) and Chinese (OR = 1.60, 95% CI 1.33-1.92) women were at greatest risk for third- and fourth-degree laceration. Only Filipino (OR = 1.32, 95% CI 1.10-1.57) and other Asian (OR = 1.23, 95% CI 1.08-1.41) women were at slightly increased risk of vaginal laceration. No differences were seen for cervical laceration. CONCLUSION: Different ethnicities are at widely varying risk of perineal laceration, but little difference exists for vaginal or cervical lacerations. Research into the mechanisms behind this should investigate differences in perineal anatomy.

Cervix Uteri↗
PubMed2005

Postpartum follow-up of a positive purified protein derivative (PPD) among an indigent population.

OBJECTIVE: This study was undertaken to investigate the rates and predictors of follow-up and treatment for postpartum patients with a positive purified protein derivative (PPD). STUDY DESIGN: Retrospective cohort study of all women delivered at San Francisco General Hospital in 2000. All patients with a positive PPD were identified and their demographic and PPD follow-up and treatment data were collected and analyzed. RESULTS: Among the 1331 patients delivered, the prevalence of a positive PPD was 32% (n = 425). Of the 393 patients who had not been previously treated, 42% (n = 167) attended a follow-up visit with 42% of these (n = 71) actually completing 6 months of therapy. Among different ethnicities, Asian patients were more likely to follow-up at a rate of 52% (P = .03). Patients who received care from the same physician both antepartum and postpartum were more likely to attend and complete therapy at rates of 67% (P < .001) and 62% (P = .01), respectively. CONCLUSION: We found that despite the opportunity given by the interaction with the medical system during pregnancy, only 18% of patients with a positive PPD actually completed therapy.

Adult↗
PubMed2005

Cost-effectiveness analysis of prenatal population-based fragile X carrier screening.

OBJECTIVE: To investigate the cost-effectiveness of a widespread prenatal population-based fragile X carrier screening program. STUDY DESIGN: A decision tree was designed comparing screening versus not screening for the fragile X mental retardation protein 1 premutation in all pregnant women. Baseline values included a prevalence of fragile X mental retardation protein 1 premutations of 3.3 per 1000, a premutation expansion rate of 11.3%, and a 99% sensitivity of the screening test. The cost of the screening test was varied from 75 US dollars to 300 US dollars. A sensitivity analysis of the probabilities, utilities, and costs was performed. RESULTS: The screening strategy would lead to the identification of 80% of the fetuses affected by fragile X annually. Assuming the cost of 95 US dollars per test and only one child, the program would be cost effective at 14,858 US dollars per quality-adjusted life-year. The screening strategy remained cost effective up to 140 US dollars per test and 1 child per woman or for 2 children per woman up to a cost of 281 US dollars per test. CONCLUSION: Population-based screening for the fragile X premutation may be both clinically desirable and cost effective. Prospective pilot studies of this screening modality are needed in the prenatal setting.

Cost-Benefit Analysis↗